Effect of Simvastatin on Nitric Oxide Production and Lipid Peroxidation of Chondrocytes.

Abstract

RATIONALE: Since statins possess anti-inflammatory properties independent from their capacity to inhibit cholesterol synthesis, we investigated the effect of simvastatin on in vitro production of nitric oxide (NO) and lipid peroxidation of inflammatory activated chondrocytes.METHODS: For NO experiments (n=4) bovine chondrocytes were stimulated for 48 h with IL- 1α and TNF-α (10 ng/mL) and pre- and co-incubated with simvastatin (0.5, 5, 10, 50 μmol/L). NO was measured as nitrite using the Griess reaction and results expressed as μmol/L. For detection of lipid peroxidation (n=5), chondrocytes were labelled with C11-BODIPY and pre-incubated (30 min) with different concentrations of simvastatin (2, 10, 50 μmol/L). Lipid peroxidation was initiated by t-butyl hydroperoxide (5 mmol/L). Fluorescence intensity was measured flowcytometrically and expressed as % oxidation (mean green fluorescence / (green+red fluorescence) ∗ 100).RESULTS: After 1 h pre-incubation with simvastatin at 50 μmol/L a significant decrease in NO production was found (36%, p<0.01). After 24 h and 48 h pre-incubation, all tested concentrations inhibited NO production, varying between 29% and 93% (p<0.03). For lipid peroxidation, a small, but significantly decrease (18%, p<0.05) was found for the highest concentration simvastatin (50 μmol/L). As a control, Trolox (100 μmol/L), which is a known antioxidant, clearly inhibited the lipid peroxidation (78%, p<0.05).CONCLUSIONS: These data indicate that simvastatin might have anti-inflammatory effects on activated chondrocytes especially by inhibition of the stimulated NO production. Its effect on lipid peroxidation was less pronounced. RATIONALE: Since statins possess anti-inflammatory properties independent from their capacity to inhibit cholesterol synthesis, we investigated the effect of simvastatin on in vitro production of nitric oxide (NO) and lipid peroxidation of inflammatory activated chondrocytes. METHODS: For NO experiments (n=4) bovine chondrocytes were stimulated for 48 h with IL- 1α and TNF-α (10 ng/mL) and pre- and co-incubated with simvastatin (0.5, 5, 10, 50 μmol/L). NO was measured as nitrite using the Griess reaction and results expressed as μmol/L. For detection of lipid peroxidation (n=5), chondrocytes were labelled with C11-BODIPY and pre-incubated (30 min) with different concentrations of simvastatin (2, 10, 50 μmol/L). Lipid peroxidation was initiated by t-butyl hydroperoxide (5 mmol/L). Fluorescence intensity was measured flowcytometrically and expressed as % oxidation (mean green fluorescence / (green+red fluorescence) ∗ 100). RESULTS: After 1 h pre-incubation with simvastatin at 50 μmol/L a significant decrease in NO production was found (36%, p<0.01). After 24 h and 48 h pre-incubation, all tested concentrations inhibited NO production, varying between 29% and 93% (p<0.03). For lipid peroxidation, a small, but significantly decrease (18%, p<0.05) was found for the highest concentration simvastatin (50 μmol/L). As a control, Trolox (100 μmol/L), which is a known antioxidant, clearly inhibited the lipid peroxidation (78%, p<0.05). CONCLUSIONS: These data indicate that simvastatin might have anti-inflammatory effects on activated chondrocytes especially by inhibition of the stimulated NO production. Its effect on lipid peroxidation was less pronounced.